Combination chemotherapy is harsh. The drugs are poisons. Side effects can be severe. Nausea and vomiting, while better controlled today, remain a problem. Weakness, fatigue, low white blood cell counts, infections, hair loss, and nerve damage, the list is long.
There are also significant long-term problems, including heart disease, brain dysfunction, hearing loss and the development of new cancers. Most anticancer drugs are carcinogenic. Nonetheless, the fact remains that almost every person that has ever been cured of metastatic cancer has been cured by "combination" chemotherapy (a small number of patients have been cured by immunotherapy). The approach has proven successful in a wide range of cancers (Frei E. et al, Cancer Res. 1985 Dec;45:6523-37).
The problem is that combination chemotherapy has run into a brick wall. It has not proven possible to extend the success of combination chemotherapy in childhood cancers, leukemia, lymphoma, and testicular cancer to cancer in general. The common metastatic cancers such as breast, lung, colon, prostate, bladder, kidney, melanoma, ovarian, and pancreatic have resisted cure by combination chemotherapy.
It is not that there has been no progress, but it has been painfully slow and limited. All too often patients and their physicians are confronted with the depressing task of balancing the severe side effects of chemotherapy and their negative impact on the quality of life against potential survival benefits.
The second reason that cure has been largely abandoned as a research goal is the complexity of the disease. What previously had been hidden is now exposed to plain view. We can now look inside the black box of the cancer cells. What we see is chaos. Every cell is different, and the cancer cells keep changing, even in the same patient.
The problem is tumor cell evolution. To achieve cure, therapy must address the problem of tumor cell evolution. Cancer can be cured. This is a fact. Thousands of patients are alive today, cured of metastatic cancer.
In 1985 Dr. Frei wrote: "To the extent that physicians and investigators are ambivalent with respect to the term 'cure,' patients and the medical community will be skeptical. One of the obstacles to progress in cancer therapy generally and in cancer chemotherapy specifically has been the presence of such skepticism" (Frei E. et al, Cancer Res. 1985 Dec;45:6523-37).
Reference: "Cure: Scientific, Social and Organizational Requirements for the Specific Cure of Cancer" A. Glazier, et al. 2005
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